Childhood sweethearts Celeste (Rashida Jones) and Jesse (Andy Samberg) call it quits after six years of marriage. Back off, I'm not spoiling the ending. That's how this breath of fresh comic air begins. Celeste is on a career high, spotting hot trends for an L.A. marketing company. When artist-wanna-be Jesse settles for slacking, alpha-girl Celeste loses her patience. But even after the split, they stay besties, sharing in-jokes like mock jerking off any handy pencil or banana. Their bond is hell on their mutual friends (Ari Graynor and Eric Christian Olsen), and especially on their dating lives. As expected, Jones (Parks and Recreation) and Samberg (a former SNL VIP) nail every laugh. More surprisingly, they also play their characters for real, letting confusion and hurt seep in between the sillier setups. Jones, who co-wrote the sharply funny and touching script with actor Will McCormack, is simply glorious. And Samberg shines in a grounded performance that digs deep. He mixes it up with a terrific McCormack, as his pot-addled pal, and Jones confides in her gay co-worker (Elijah Wood). And yet those sitcom staples don't sink the ship. Credit director Lee Toland Krieger, of the underrated The Vicious Kind, for keeping just the right emotional balance as Celeste alienates a series of suitors (Rafi Gavron, Chris Messina) and Jesse tries to do the right thing by a pregnant one-night stand (Rebecca Dayan). What really lifts Celeste and Jesse Forever above the rom-com herd, besides breakout star performances from Jones and Samberg, is the movie's willingness to replace clichés with painful truths. It's irresistible.